USB devices not working on systems with legacy BIOS

[NiKiZe]

for reference this relates to the discussion at http://forum.ipxe.org/showthread.php?tid...0#pid13480

Default builds of iPXE does not have USB support enabled.
So to get this kind of issue you need to have built something "special" so it might be a good idea to share you exact build command and configuration.

The only way to use USB is for the system to load it's own drivers since there is no standard for using already existing "drivers" in regards to USB, (and for the few platform where such interfaces exist it is unusable slow)

So when iPXE starts and has USB drivers enabled it loads it's own stack to access USB devices, and loads it own drivers for keyboard. (for anyone else reading note that there is no mass storage support)
Once iPXE exits "all" drivers are shut down and any other software is free to do whatever it want's to do.

In BIOS mode AFAIK there is no call that can be made to get original drivers to re-enumerate the bus.

So this is not an issue of releasing the USB controller, but rather that BIOS can not reclaim the controller regardless of what iPXE does or not.


As a work-around my suggestion is to instead use the iPXE menu system, and wimboot with different BCD files to get the menu options you want. The alternative is to not use USB enabled iPXE, or using a PS/2 based keyboard instead of USB.